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Old 22-10-2010, 02:37 PM
NGC2264 (Gordon)
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Join Date: Feb 2009
Location: City
Posts: 18
Jowel,

I have the sky watcher 10" collapsible dobsonian and I love it - a great first telescope in my opinion. I went with the collapsible because I didn't have enough room for the solid tube either in storage or carting it around. For me the collapsible was the way to go. Of course you realise that once you get the 10", six months later you'll wish you got the 12"

In terms of collimation I have both the laser collimator and a Cheshire cross-hair piece collimator. You'll hear people say laser collimators aren't as accurate as cheshire collimators. And then you'll find the old school folk who say that the only way to really collimate a telescope is by doing it on a star without any device.

A laser collimator is fine so long as the laser itself is collimated. The easy way to determine this is to put it into the eyepiece holder and rotate it around. Watch the dot on the primary mirror and see if the dot moves around. If it stays in the same spot then the laser collimator is good. if it moves around then you have a problem with your device and it needs to be adjusted.

One advantage of a laser collimator over a Cheshire is that when you are out in the dark viewing and you need to collimate your scope, Cheshire is useless and the laser is what you need unless you know how to collimate it using a star. I got my laser collimator from York Optical and it was just fine.

In collimating the 10" collapsible I found that trying to adjust the secondary mirror was really hard work. The screws were really hard to turn. Thankfully I have never really had to do it. Adjusting the primary mirror was actually the easiest part of the process.

As with everything to do with astronomy, you've just got to dive in and do it. The more times you do it, the more confortable you will about doing it.
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